1. Field of the Invention
The invention concerns cosmetic compositions with enhanced photoprotection properties.
2. The Related Art
Many people dislike northern climates. There is a longing to bask in the warmth of the sun. Days at the beach find us in swimsuit attire. Many seek to turn their pale winter skin into a bronzed appearance. Others of naturally darker skin simply enjoy the refreshment of the seashore. Without protection from harmful ultraviolet radiation damage, these pleasures can turn into premature aging. Skin can loose elasticity and wrinkles appear in the premature aging process. Radiation can promote erythemal damage, can cause photo allergic reactions, and is implicated in skin cancers.
Protective measures are necessary. Lotions and creams formulated with sunscreens can shield against ultraviolet damaging radiation. The extent of protection varies widely.
Numerous ultraviolet photoprotective (sunscreen) agents are known. Nonetheless, only a small number are both commercially available and approved by regulatory authorities. A need exists to operate with known approved commercial sunscreen agents yet formulating them to achieve more than their expected level of photoprotection.
Representative of the art is U.S. Pat. No. 5,961,961 (Dobkowski et al.) reporting enhancement of the photoprotective effect by utilizing relatively large particle size titanium dioxide coupled with an organic sunscreen agent. Representative organic sunscreen agents include Benzophenone-3, octyl salicylate, octyl methoxycinnamate and 2-phenylbenzimidazole-5-sulphonic acid.
Certain types of cosmetic systems are particularly difficult to adequately fortify with photoprotective agents. A particular example is that of stearate structured gel systems containing small amounts of potassium stearate.